1. Field of the Invention
The present invention relates to an earphone, and more particularly to a structure capable of simplifying the earphone, and a structure allowing the earphone to have a better sound effect.
2. Description of Related Art
A portable electronic device with a voice output function such as cellular phone or AV player may mostly be coupled to an earphone to provide a user with a better voice listening function.
A speaker unit must be coupled into a housing of a general earphone to be used as a voice output unit. As an example, an insert type earphone disclosed by Taiwan Patent No. M324935 comprises a housing, a rear portion of the housing is disposed with an indentation portion, a sounding element is fixed in the housing, and the sounding element is connected with a lead. There are various patents concerning speaker unit, for example, a frame structure for a mini-earphone speaker disclosed in Taiwan Patent No. 68550 and an earphone type loudspeaker disclosed in Taiwan Patent No. 504099.
In the earphone type loudspeaker mentioned above, components such as a magnet, a pole piece, a voice coil, a diaphragm and a protection cover are placed in sequence in a central ring indentation portion of a bottom shell thereof, a bottom of a rim wall of the bottom shell is coupled to a terminal strip for allowing pair wiring of the voice coil to be passed through and bonded thereon and a circumference of the diaphragm is further pre-stuck with a metal ring; an annular rim face of the bottom shell is formed to be a open plain portion, and sizes of the components such as the diaphragm, the metal ring and the protection cover are also allowed to be extended to a diameter size of the bottom shell to enable the diaphragm to be attached along the plain portion of the annular rim face of the bottom shell to form an even-jointed combination to expand an area of the diaphragm and further to obtain an effect of a broader compass of voice.
The earphone type loudspeaker mentioned above is still necessary to be coupled to the earphone shell to assemble into an earphone, and the diaphragm must be pre-stuck with a metal ring; it will increase the material and assembly costs. Moreover, there is no design of rear resonant chamber in the earphone type loudspeaker; the earphone will not obtain a better bass effect.